The United States declared Venezuela a national security threat and ordered sanctions against seven officials from the oil-rich country. The US move has triggered "anti-imperialist" rallies, military exercises and a proliferation of graffiti condemning "gringo" interference.

A woman walks past anti-US graffiti in CaracasJorge Silva/ReutersA man walks past graffiti depicting US President Barack Obama and the slogan "The bombs have no name" in CaracasCarlos Garcia Rawlins/ReutersA woman rides a motorbike past graffiti reading: "Gringo, respect us!" in CaracasJorge Silva/ReutersA portrait of Chavez and an anti-American slogan are daubed on a wall in CaracasFederico Parra/AFPA stencil depicts a dog with Obama's head and the slogan "Barking dogs seldom bite"Federico Parra/AFP

Venezuelan President Nicolas Maduro denounced the sanctions as an attempt to topple his government. It accused Washington of planning military attacks and wider Cuba-style trade sanctions. State TV has been playing old footage of the US invasions of Grenada and Panama.

"President Barack Obama... has personally decided to take on the task of defeating my government and intervening in Venezuela to control it," Maduro said in a televised address. The embattled president denounces the Yankee empire almost nightly on national television.

Workers of state-run oil company PDVSA hold a giant picture of Venezuela's late president Hugo Chavez during a rally against US imperialism in CaracasCarlos Garcia Rawlins/ReutersWorkers of state-run oil company PDVSA take part in a rally against US imperialism. The placard reads: "The oil is ours, Yankees go home"Carlos Garcia Rawlins/ReutersBolivarian militia wearing the uniform made famous by Chavez, shout anti-US slogansJuan Barreto/AFPSupporters of Venezuelan President Nicolas Maduro take part in a demonstration against the USJuan Barreto/AFPA woman holds a sign saying: "This is how much I care about your sanctions, Mr Obama"Federico Parra/AFP

The US is inadvertently enabling Maduro to play the nationalist card skilfully employed by his charismatic mentor Chavez, whose populist style and focus on social welfare made him hugely popular among the poor for most of his 1999-2013 rule.

Opposition politicians said Maduro was cynically exploiting the diplomatic flare-up with Washington to amass powers, justify repression and distract Venezuelans from economic problems including acute shortages.

Supporters of President Maduro protest against "Imperialist aggression"Federico Parra/AFPA woman walks past graffiti reading: "Venezuela belongs to us, not gringos or traitors" in CaracasFederico Parra/AFPA supporter of Maduro protests against the United States, during a demonstration in CaracasFederico Parra/AFPA Maduro supporter holds a placard featuring Obama with devil's hornsJuan Barreto/AFP

The sanctions effectively confirm Venezuela as the US's primary adversary in Latin America, a label that was for decades applied to Communist-run Cuba until Washington and Havana announced a diplomatic breakthrough in December 2014.